1.4 & 1.5 - Cells

Question 1

What are the 4 things a cell must have to be classified as a cell?

Answer 1

1. Be contained within a membrane
2. Have genetic material (DNA)
3. Contain metabolic enzymes
4. Be capable of replication

Question 2

What are the 4 main functions of a cell membrane?

Answer 2

1. Transport things in and out of the cell
2. Regulate what goes in and what comes out
3. Provide structure for the cell
   4 facilitate communication between other cells

Question 3

Compare and contrast:
-facilitated diffusion
-simple diffusion
-active transport

Answer 3

-facilitated diffusion: molecules move through channel proteins, move larger and polar molecules, from high to low (no energy)
-simple diffusion: move directly through bilayer, move smaller and nonpolar molecules, from high to low (no energy)
-active transport: requires a channel protein, low to high (requires energy)

Question 4

What are endo and exocytosis?

Answer 4

Don’t use protein channels - membrane engulfs molecules to form a vesicle

Question 5

Why is it important for cells to receive signals?

Answer 5

A changing environment requires cells to be able to alter their functions, also used to coordinate activities with other cells in multicellular organisms

Question 6

Why can some cells respond to a signal molecule but others can’t?

Answer 6

Cells have to have a specific receptors protein that matches their molecule to be able to receive and respond to signal molecules